Self seal-in a. c. operated relay



R. J., coPPoLA 1 sm' SEAL-IN A. OPERATED RELAY June 9, 1959 Filed larch5, 1956 2 Sheets-Shut 1 Fig. 1

Fig. 3

-34 POWER SOURCE LOAD INVHVTOR. RICHARD J. COPPOLA.

June 9, 1959 R. J. COPPOLA saw SEAL-IN A.C. OPERATED RELAY I 2Sheets-Sheet 2 I Filed larch 5, 1956 INVENTOR. RICHARD J. COPPOLA LOADPOWER SOURCE A'T rorauwgvi United States Patent SELF SEAL-IN A.C.OPERATE-D RELAY Richard J. Coppola, Levittown, Pa.

Application March 5, 1956, Serial No. 569,663

9 Claims. (Cl. 317-156) (Granted under Title 35, US. Code (1952), see.266} The invention described herein may be manufactured and used by orfor the Government of the United States of America for governmentalpurposes Without the payment of any royalties thereon or therefor.

The present invention relates to a self seal-in A.C. operated relay andmore particularly to an A.C. relay that will operate from polyphase A.C.power controlled from one phase of this power source.

A present arrangement for a polyphase A.C. operated relay consists ofthe use of polyphase transmission lines to the operating coils. If threecoils are used, three wires and a three-pole switch must be employed tocontrol the On and Off positions of the relay.

The aforementioned arrangement requires multipole control switches andthe use of more than one wire to the control coils of the relay. This isa construction which is relatively expensive and especially disadvantageous when the relay is to be used aboard aircraft or other mobile typeequipment where size and weight are critical factors.

The present arrangement utilizes a plurality of stationary C cores, eachprovided with a matching core mounted for rotation. Each pair ofstationary and movable cores is provided at the air gap with a coilsupplied with a voltage from a diiferent phase from that of the nextcoil. One of said coils is connected directly, through a switch, to thepower source, while the remaining coil orcoils are connected through therelay contacts to the powersource. The movable cores are joined togetherto form a single armature which is arranged to close the relay contactsupon closing the air gaps between movable and stationary cores. Byclosing said switch, the armature is caused to close for an instant.This energizes the remaining coils and insures fluxes in these coresthereby maintaining the relay in its actuated position. In this way therelay operates from polyphase A.C. power through the use of only oneline from one phase.

An object of the present invention is the provision of a polyphase relayoperable and controlled from single phase A.C. power.

Another object is to provide a polyphase A.C. relay which is simple inconstruction and highly resistant to shock and high frequency vibration.

A further. object of the invention is the provision of a polyphase relaycontrolled from single phase A.C. power having a pickup coil forinitially actuating the relay and a seal-in coil for locking the relayin the actuated position.

Still another object is to provide a polyphase A.C. relay utilizing onephase for initially actuating the relay and the. other phases formaintaining said relay in its actuated position.

Other objects and advantages of the invention will hereinafter becomemore fully apparent from the following description of the annexeddrawings wherein:

Figs. 1, 2 and 3 show, schematically, a preferred embodiment of theinvention.

2,890,393 Patented June 9, 1959 Fig. 4 shows voltage vectors of thepower source explaining the principle of operation of the invention ofFigs. 1-3.

Figs. 5, 6 and 7 illustrate an alternate arrangement of the invention.

Referring now to the drawings, wherein like reference charactersdesignate like or corresponding parts'throughout the several views,there is shown in Figs. 1, 2 and 3 one preferred form of the relay. Fig.1 shows the 0, cores 10, 12, 14 and 16 mounted in a manner to bedescribed. Cores 10 and 16 are stationary and may be mounted by anyconventional means directly on a supporting plate 18. The aforementionedcores may be of any suitable type including that described in myapplication Serial No. 560,467, filed January 20, 1956. Cores 12 and 14are joined together at their common surface 20 forming an armature 13mounted for rotation on a shaft element 22 which is directly connectedto plate 18. An insulating layer may be placed along surface 20separating the two cores 12 and 14. Aspring 24 orany other means may beselected for providing bias for armature 13 in its deactivated positionagainst stop element 26. A pair of coils I and I are mounted across theair gaps between respective cores 10, 12 and 14, 16 for inducing fluxinto the core and armature elements. It will be noted that core pairs10, 12 and 14, 16 provide a pair of complete magnetic circuits 15 and17', as illustrated in Fig. 3. Armature 13 is also provided with abracket 28 for hingedly connecting a rod element 31?, which, as shown inFig. 2, is connected to a multipole switch 32.

As shown in Fig. 2, power source 34 provides threephase power throughlines A, B and C, respectively, to load 39. Multipole switch 32comprises a series of con tacts 35, 36 and37 for closing. the connectionbetween the source and the load ends of three-phase lines A, B and C.Switch 32 also includes a fourth contact 38 which closes an electricalconnection across phase lines, B and C through seal-in coil 1 forreasons to be further explained. Between line A on the power source sideof contact 35 and ground is provided a control switch 40 for energizingpickup coil 1 Fig. 3 illustrates the coil and armature arrangement ofFig. 1 upon activation of the relay, which is described below.

The relay of Figs. 1, 2 and 3 functions as follows: Closing controlswitch 40 energizes pickup coil 1 with phase voltage V pulling armature13 in the direction of the arrow shown at the upper air gap. This actswith a pulsating torqueproduced by the alternating flux in the upperclosed loop magnetic circuit 15. As soon as switch 32 closessufiiciently by the. motion of armature 13 to thereby switch. powersource 34 to load 39, the line voltage m across transmission lines B andC, which is out of phase withv the phase voltage V across A and ground,is applied to seal-in coil. I This results in a second attractivepulsating torque at the lower air gap produced by the alternating flux17 in the lower closed loop magnetic circuit. The torque derived fromcoil 1 seals in or maintains the requisite contact pressure for switch32. With proper design, coils I and I produce equal pulsating forces ortorques at both air gaps resulting in a constant, non-pulsating,armature torque, which is the vector sum of the two individual torquesproduced by each closed loop magnetic circuit.

Fig. 4 shows vectors V V and V, representing the voltages A, Band C,respectively, of the power source.

The vector V represents the voltage in line A which coils I and I; arereached 90 apart in phase, thereby providing at all times a field onarmature 13 maintaining it in its closed position as long as both coilsI and 1 are energized.

In order to deactivate the relay, control switch 40 is opened resultingin the deenergization of pickup coil I This will reduce the developedarmature torque to a pulsating value having an average value of one-halfthe original constant armature torque. The pulsating torque will permitbreaking of the contacts in switch 32 and the subsequent deenergizationof seal-in coil I The relay will stay in this position until controlswitch 40 is closed again. Contact 38 is a safety feature designed toprevent reflections from load 39 from energizing coil I when the relayis deactivated.

Figs. 5, 6 and 7 show an alternate arrangement utilizing three pairs ofC cores and three coils. Referring to Fig. 5, movable cores 52, 54 and56 are mounted on a shaft 58 while means such as a plate 60 may beutilized to insure that the cores move in unison as a rigid armaturestructure 62. Stationary cores 64, 66 and 68 are provided to match theirrespective movable cores as described in connection with Fig. l. Coils I1., and I are provided across the air gaps in the same manner as isdescribed in connection with Fig. 1. (not shown) for maintainingarmature 62 in its position of Fig. 5 when not activated, and stop means(not shown) for limiting the deactivated position of armature 62 may beprovided by any means well known to those skilled in the art. Fig. 6shows a multipole switch 70 having an arm 72 which may be connected inany conventional manner, such as shown in Fig. 1, to armature 62. CoilsI I and I are connected to transmission lines B, C, and A, respectively.

In the operation of this embodiment, when switch 74 is closed, pick-upcoil I upon reaching its maximum pulse, closes armature 62 in thedirection of the arrow shown, thereby resulting in the instantaneousclosing of multipole switch 70. This provides the power to the loadthrough lines A, B and C and also acts to energize coils I and I It willbe noted that since each of the coils is connected between a singletransmission line and a mutual ground point, each coil receives voltagesV,,, V V,,, respectively, as shown in Fig. 4. It will be seen that thesevectors are 120 apart in phase, thereby providing for an equal voltageat each of the coils spread equally 120 apart. The average developedtorque of this arrangement runs approximately 50 percent greater thanthe average torque produced as a result of the arrangement of voltagevectors in the arrangement of Figs. 1, 2 and 3. Thus, this arrangementwould be highly resistant to shock and vibration tending to knockarmature 62 out of its energized position.

It will be seen that the inventive relay described above is advantageousin many ways. The relay utilizes a single pole switch for the actuationand control of the relay and single wire transmission between the switchand relay. The construction of the inventive relay enjoys the advantagesof polyphase operated devices without sacrificing the advantages ofsimplified controls of single phase devices. Also, a reduced drop-outvoltage results from this construction as would be encountered when thethree-phase system voltage drops under system fault conditions.

Obviously, many modifications and variations of the present inventionare possible in the light of the above teachings. It is, therefore, tobe understood that with in the scope of the appended claims theinvention may be practiced otherwise than as specifically described.

What is claimed is:

1. A self seal-in relay for use in a polyphase transmission systembetween a power source and a load, comprising, a movable armature,contact means movable with said armature including a contact in eachphase Bias means line of said transmission system, said armature movablebetween a first, normal position wherein each said contact is open and asecond, energized position closing each said contact, stationary coremeans forming with said armature at least two magnetic circuits, whereinflux induced tends to urge said armature from said first position intoits said second position, first means adjacent said core means capableof inducing flux into the first of said magnetic circuits, meansincluding a switch which upon closing connects said first means directlyto one phase of said power source for inducing flux in said firstmagnetic circuit causing rotation of said armature into said secondposition closing each said contact, second means adjacent said coremeans capable of inducing flux into the second of said magneticcircuits, and means connecting said second means to another phase ofsaid power source through the contact therein when closed for inducingflux in said second magnetic circuit thereby sealing said armature inits energized position by providing continuous flux inducement in saidarmature.

2. A self seal-in relay for use in a polyphase transmission systembetween a power source and a load, comprising, a movable armature,switch means in each line of said transmission system movable with saidarmature, said armature movable between a first, normal position whereineach said switch means is open and a second, energized position closingeach said switch means, stationary core means forming with said armatureat least two magnetic circuits, wherein induced flux urges said armaturefrom said first position into its said second position, first coil meansadjacent said core means capable of inducing fiux into the first of saidmagnetic circuits, means selectively connecting said first coil meansdirectly to one phase of said power source for inducing flux in saidfirst magnetic circuit causing rotation of said armature into saidsecond position closing each said switch means, second coil meansadjacent said core means capable of inducing flux into the second ofsaid magnetic circuits, and means connecting said second coil means toanchor phase of said power source through the switch means therein whenclosed for inducing flux in said second magnetic circuit thereby sealingsaid armature in its energized position by providing continuous fluxinducement in said armature.

3. A self seal-in relay for use in a polyphase transmission systembetween a power source and a load, comprising, a movable armature,contact means movable with said armature including a contact in eachphase line of said transmission system, said armature movable between afirst, normal position wherein each said contact is open and a second,energized position wherein each said contact is closed and provides anunbroken circuit, stationary core means forming with said armature atleast two magnetic circuits, wherein flux induced tends to urge saidarmature from said first position into its said second position, a firstcoil adjacent said core means capable of inducing flux into the first ofsaid magnetic circuits, means including a switch which upon closingconnects said coil directly to one phase of said power source forinducing flux in said first magnetic circuit causing rotation of saidarmature into said second position closing each said contact, a secondcoil adjacent said core means capable of inducing flux into the secondof said magnetic circuits, and means connecting said second coil toanother phase of said power source through the contact therein whenclosed for inducing flux in said second magnetic circuit thereby sealingsaid armature in its energized position by providing continuous fluxinducement in said armature.

4. A self seal-in relay for use in a polyphase transmission systembetween a power source and a load, comprising, a movable armature,contact means movable with said armature including a contact in eachphase line of said transmission system, said armature movable between afirst, normal position wherein each said contact means is open and asecond, energized position wherein each said contact means is closed,stationary core means forming with said armature at least two magneticcircuits, wherein flux induced tends to urge said armature from saidfirst position into its said second position, first means adjacent saidcore means capable of inducing flux into the first of said magneticcircuits, switch means upon closing for connecting said coil directly toone phase of said power source for inducing flux in said first magneticcircuit causing rotation of said armature into said second positionclosing each said contact, second means adjacent said core means capableof inducing flux into the second of said magnetic circuits, meansconnecting said second means to another phase of said power sourcethrough the contact therein when closed for inducing flux in said secondmagnetic circuit thereby sealing said armature in its energized positionby providing continuous flux inducement in said armature, and saidcontact means provided with another contact in said last namedconnecting means for preventing reflections from said load fromenergizing said relay when said switch means is open.

5. The relay of claim 4 in which said contact means consists of each ofsaid contacts ganged to close and open in unison upon movement of saidarmature.

6. A self seal-in relay for use in a polyphase transmission systembetween a power source and a load, comprising, a movable armature,contact means movable with said armature including a plurality ofcontacts at least one of which is in each line of said tranmissionsystem, said armature movable between a first, normal position whereinsaid contacts are open, and a second, energized position closing saidcontacts, stationary core means forming with said armature a pair ofindependent magnetic circuits wherein flux induced urges said armaturefrom said first position to said second position, first coil meansadjacent said core means capable of inducing flux into the first of saidmagnetic circuits, means including a switch which upon closing connectssaid first coil means to one phase of said power source on the powerside of said contact means for inducing said flux and causing rotationof said armature into said second position closing said contacts, secondcoil means adjacent said core means capable of inducing flux into thesecond of said magnetic circuits, and means connecting said second coilmeans between the second and third phases of said power source on theload side of said contact means thereby energizing said second coilmeans upon said armature being moved into its said second position.

7. A self seal-in relay for use in a polyphase transmission systembetween a power source and a load, comprising, a movable armature,contact means movable with said armature including a plurality ofcontacts at least one of which is in each line of said transmissionsystem, said armature movable between a first, normal position whereinsaid contacts are open, and a second, energized position closing saidcontacts, stationary core means forming with said armature a pair ofindependent magnetic circuits wherein flux induced urges said arma turefrom said first position to said second position, first coil meansadjacent said core means capable of inducing flux into the first of saidmagnetic circuits, means including a switch which upon closing connectssaid first coil means to one phase of said power source on the powerside of said contact means for inducing said flux and causing rotationof said armature into said second position closing said contacts, secondcoil means adjacent said core means capable of inducing flux into thesecond of said magnetic circuits, means connecting said second coilmeans between the second and third phases of said power source on theload side of said contact means thereby energizing said second coilmeans upon said armature being moved into its said second position, andsaid contact means provided with an additional contact in said lastnamed connecting means to prevent energization of said relay due toreflections from said load.

8. A self seal-in relay for use in a polyphase transmission systembetween a power source and a load, comprising, a movable armature,contact means movable with said armature including a contact in eachline of said transmission system, said armature movable between a first,normal position wherein each said contact is open, and a second,energized position closing each said contact, stationary core meansforming with said armature three independent magnetic circuits whereinflux induced therein urges said armature from said first position tosaid second position, means adjacent said core means capable of inducingflux into the first of said magnetic circuits, means including a switchwhich upon closing connects said coil directly to one phase of saidpower source for inducing said fiux and causing rotation of saidarmature into said second position closing each said contact, second andthird coils adjacent said core means capable of inducing flux into thesecond and third of said magnetic circuits, respectively, and meansconnecting said second and third coils to second and third phases,respectively, of said power source on the load side of the respectivecontacts in each phase closed by movement of said armature, therebysealing said armature in its second, energized position.

9. A self seal-in relay for use in a polyphase transmission systembetween a power source and a load, comprising, a movable armature,contact means movable with said armature including a contact in eachline of said transmission system, said armature movable between a first,normal position wherein each said contact is open, and a second,energized position closing each said contact, stationary core meansforming with said armature three independent magnetic circuits whereinflux induced therein urges said armature from said first position tosaid second position, means adjacent said core means capable of inducingflux into the first of said magnetic circuits, means including a switchwhich upon closing connects said coil directly to one phase of saidpower source for inducing said flux and causing rotation of saidarmature into said second position closing each said contact, second andthird coils adjacent said core means capable of inducing flux into thesecond and third of said magnetic circuits, respectively, meansconnecting said second and third coils to second and third phases,respectively, of said power source on the load side of the respectivecontacts in each phase closed by movement of said armature, therebysealing said armature in its second, energized position, and saidcontact means also including safety contacts in said last-namedconnecting means to prevent energization of said relay due to feedbackfrom said load while said relay is deactivated.

References Cited in the file of this patent UNITED STATES PATENTS969,809 Simon Sept. 13, 1910 2,426,062 Sonnemann Aug. 19, 1947 2,591,520De Fligue Apr. 1, 1952 FOREIGN PATENTS 512,735 Great Britain Sept. 25,1939 1,059,953 France Mar. 30, 1954 UNITED STATES PATENT OFFICECERTIFICATE OF CORRECTION Patent NOD 2,890,393 June 9, 1959 Richard JCoppola It is hereby certified that error appears in the printedspecification of the above numbered patent requiring correction and thatthe said Letters Patent should readas corrected below.

Column 2, line 71, for "voltage vector V read w voltage vestor V column4, line 39', for "anchor" read another Signed and sealed this 29th dayofIvIarch 19600 (SEAL) Attest:

KARL Ha AXLINE ROBERT (J. WATSON Attesting Officer Commissioner ofPatents UNITED STATES PATENT OFFICE CEBTIFIQATE OF CORRECTION Patent Non2,890,393

June 9, 1959 Richard J a Coppola It is hereby certified that errorappears in the printed specification of the above numbered patentrequiring correction and that the said Letters Patent should read ascorrected below.

'r Column 2, line '71, for "voltage vector V read voltege ves tor Vcolumn 4, line 39, for "anchor" read another Signed and sealed this 29thday ofivlerch 1960.,

SEAL) Attest:

KARL Ha AXLINE ROBERT C. WATSON Attesting Officer Commissioner ofPatents

